Valve for rock drills



Feb. 16 1926. 1,573,457

F. M. sLATER VALVE FOR Rocx DRILLSv Filed oct. 24, 1923 nl u % HISATTOR Y Patented Feb. 16, 1926.

Gili FlfCfEm y FREDW. 'SIQATERQ UFEALVSTON; IEENNSYTJVANIA,AASSIGNUR.TU INGERSOTJLPRAND`COML PANY'OF J'ERSEY`CITY`, NETJERSEY, A CORPORATION" 0F NEWT JERSEY.

VLV-E- FOR* ROCK DRLLS.

Application,led'fctober'zll, 1923; ScrialNo. 670,396.

[ aZZ whom at' mcg/comercia will start the hammer pistonl i'nl operation regardless of thepositioirin which the rock. drill: isheld,. and will continue `to function Be it knownithat I, Fiano M; SI1-Armee citizenL ofthe-United- States,j and a resident of Easton, county loi" Northampton,` and` State of Pennsylvania, have.` inventeda cer tain: Valve for Rock Drills, of which the followingwis a: speciticatioin;accompanied by drawings.

This invention relates to fluid"` actuated rock drills, butfmoreparticularly toia-.tluid actuated valve=ot tlie'spool type, controlling toiobtainf an inlet valve which is quick and positive inaction, delicately-balancech and eitectively controlled by, the livewair andfby the-exhaust from theunai'n cylinder;

Other objectsfofs'the inventionzare topro-V ducea valve ofttheitype referred to, which automatically unden substantially all i condi;- tionsthusdeepingf the piston; in; continuous operation.

Furtherobjects: of theinvention are to prei/*ent the valve from: centering: or stopf ino'V at times which isA a; serious disad- P e a vantage itV such stoppage occurs, and `onthe other hand,iit the pistoni tends `to stop'y or, actually comesto rest' 4inthe 4length/oli` the cylinder for any reason, this improved valve Willi automatically become` unbalanced ovving tothe` construction ot thef ports `and passages and will be; thrown ini a direc tion .toimmediately start the piston in operation again.

i/v'alves of this type,` orfin fact of" any typeu operating in conjunction: vvith a free exhaust from the cylinder, should not pass moreV air than; can be. easily taken care of by the exhaust, `nor should-` they pass too little air, so that theA valveV travel should be either too greatl non too small, and the valve should be properly timed to produce the requisitevnumber off hammenbloivs per minute of requisite strengthe and etliciency, as otherwise the `drilling will be r reduced.

Allthough for simplicity oit illustratiom the valveis shown applied tota handheld drill, thisr valve is-especially suitable fon a stops drill ofl the hammer.type,fhaving rifle ban rotation, and a.- fluid pressure `feeding element, such asan-air feedcylinder. A rifle bar stoper having' air feed, throws extra Work upon the hammer piston, owing to thel continued pressure of the feeding elementand the valve must i'unction positively,

in order to` keep tho rotating hammer 1n ulloperation and striking powerful blows un der the most severe conditions.

The invention is illustrated in one of its preferred forms in the accompanying drawings, in which- Figure l` is a longitudinalV sectional elevaL tion of a fluid' actuated rock drill having the improved valve applied thereto,

Figure 2 is'a-detaillongitudinal sectional elevation otra portion-of the machine-showingthevalve in a. ditfcrentposition from that indicated in Figure l, and

Figure 3 is an enlarged detail longi tudinal sectional View taken through the valve and valve-chest.

Reiierring tothe drawings, the rock drill to whichl my valve is applied, for purposes ot illustration, comprises a cylinder ik hav-` ingva reciprocating piston Bfprovided with a head C and a shank D adapted `to-impar: blows of impact to the shank ot the drill steel EI extending into the chucky F in the lront head G in positioitto `be struck by the piston. A- front cylinder extension H may be interposed between the cylinder and front headiG and the parts may beheldt-of getherf bythefusual side bolts, not shown.

In thisinstancaa rock drill havingauto matic rotation, is illustrated,` and the-shank D- of the piston is.. provided with the flutes .l engaging the flutes K on thechuck F. rifle bar Lfengages the piston and extends through the back cylinder Washer O and is formed, with theusual ratchet P cooperate ingwith the rotation ratchet ring Q- over which is placed the back rotation Washer R. rock drill-inrany. convenient manner.

A valve chest T is located at one side ol the cylinder and motive liuid,` in this in A- suitable handle S is connected tothe 'that the opposed edges g and t at the meeting faces of' the bushings are separated by a space Vopposite the groove j in the Yvalve chest,so that an annular inlet port is formed at this point opposite the inlet U. The valve 0 is formed with the end heads 70 and 0 and a central flange p of larger diameter than the heads, which flange controls the passage of motive fluid from the inlet U to both ends of the cylinder A, The flange 7) as shown extends into the annular port between the meeting edges g and 7i of the valve bushings, and as the valve reciprocates, the said flange seats upon said opposed 'edges g and h which also form stops limiting the movement of'- the valve. annular shoulders p are formed on the valve at each side of the flange y? and these shoulders preferably have sliding contact with the bore of the bushings X. and Y, as the valve reciprocates. ln consequence, although the travel of' the valve is reduced to a minimum between the opposed edges g and tof the valve bushings, the actual portopenings are controlled by the annular flanges 2) and the valve openings or spaces allowed for the passage of air-between the flanges p and the edges g and L of the bushings are of less n width than the actual valve travel, so that only suliicient airis passed for obtaining maximum efficiency in the operation of the rock drill. The free exhaust .e in the cyllinder A controlledby the piston, is preferably designed with relation to the ports controlled by the valve flange jj to obtain maximum efficiency.

' The valve bushings X and Y are. formed with the lportsV g and 1 registering with the passages s and t, which in this instance cross Y'each other and lead to the opposite ends of the cylinder for supplying motive fluid to the cylinder for the operatien ot' the hammer piston. rl`he bushings X and Y are also provided with the atmospheric leali ports u vand e preferably connected by grooves or passages w and a@ to the ports fw and e in the valve bushings, which in turn communicate with the atmosphere through the ports fw and in the valve chest. flhe atmospheric leali ports u. and e in the valve bushings are so located that they are controlled by the ends 0 and 7a of the valve and alternately vent the space behind the ends of the valve to the atmosphere through the ports w. and which are always in communication with the atmosphere. rljhe ports u and Qi in the valve bushings leading to atmosphere are also controlled by the ends o and 7c of the valve and alternately place the Aends of the cylinder in communication with The valve is preferably hollow with a central web y through which small ports 2 and 3 are conveniently located preferably at an angle to the longitudinal axis of the valve, which small ports connect the inlet U direct'- ly with the spaces ai and respectively, at the ends of the valve.

The valve is positively thrown by live air, the pressure fluid passing to the ends of the valve through the small ports Z and 3, and building up pressure at that end of the valve, at which the atmospheric leak port u or e is closed, the space at the other end of the valve being open t0 atmosphere, as indicated. The valve is held by the pressure of live motive fluid on one of the faces of the central flange p, until such pressure is relieved by opening of the main exhaust e by the piston.

In the operation of the device, let it be assumed that the piston B is moving on its `forward stroke, which is about lto be com.- pleted, as indicated in Figure l. The valve c is as indicated in rearward position, and live motive fluid is passed from the inlet U Aaround the valve through the supply passage s to the rearward end of the cylinder, driving the piston forwardly. The pressure of motive iluid on the central i'lange p holds the valve in its rearward position as indicated. Motive fluid passing through the small port 2 in the valve to the space Z) at the rearward end of the valve, tends to build up pressure in the said space and partially balances but does not over-balance the pressure on the flange ,n lending to hold the valve in position. As soon as the piston head C uncovers the exhaust port e in the cylinder, the pressure on the flange p or" the valve holding the valve in its rearward position is reduced to atmosphere, `and the pressure of live motive fluid in the space l) will throw' the valve forwardly to the position indicated in Figure 2, in readiness to supply air to the forward end of the cylinder for the return of the piston. lllith the valve inthe position indicated in Figure l, the space between the flange p of the valve and the` head 7c, is open to atmosphere through the atmospheric port so that any compression pressure in front of the piston as the pistoncompletes its forward stroke is relieved through the supply passage t and the atmospheric port m.

On the return stroke of the piston, as indicated in Figure 2, with the valve in forward position, a similar cycle of events takes place. Pressure fluid is supplied from the inlet U around the valve and through the supply passage t to the forward end of the cylinder and live motive fluid also passes through the small port 3 in the valve to the spaceV a at the forward end of the valve behind the valve head 0 and pressure is built up in said space opposing lbut not overbalancing the pressure of the liveiair on the ward position. The space between the fla-nge p of the valve and the forward head 0, 1s open to atmosphere through the atmospheric Vport w so that compression pressure from the rearward end of the cylinder produced by the piston, is relieved at this point. lWhen the piston overruns the exhaust port z,

the pressure holdingthe valve in forward position is reduced to atmosphere and the live air in the space a at the forward end of the valve throws the valve to rearward position.

Since the supply passages s and t from the valve to the ends of the cylinder, cross each other, the machine is always in readiness to start operation. If it be assumed that both the piston and the valve are in their rearward positions, motive fluid will be admitted to the rearward end of the cylinder through the supply passage s to start the piston forward and if both the piston and the valve are in forward position, motive fluid will be supplied to the forward end of the cylinder to drive the piston rearward and'in either case, the valve will automatically assume its functions. On the other hand, if for instance the piston should for any reason corne to rest in the length of' the cylinder, in a position to cover the exhaust port e, the valve would automatically become unbalanced and be thrown to a position to start the piston in operation again, because the continuous building up of live air pressure in a space at one end of the valve and the continual'lealrage of pressure to atmosphere in the space at the other end of the valve, will cause the valve to be thrown over to a position to supply live air against that face of' the piston requisite to move the piston in the direction in which it can most easily move.

l claim:

l. In a fluid actuated rock drill, the combination with a cylinder and reciprocating piston of a valve chest, a fluid actuated valve controlling the inlet supply and having a single central flange of larger diameter than the ends of the valve, which flange controls the passage of motive fluid from 'the ends of the valve and a free exhaust port controlled by the piston, and atmospheric leak ports leading from the spaces at the ends of the valve and controlled by the ends of the valve, whereby the valve is thrown in a direction oppositeI to t-he direction of travel of the piston by the live motive lfluidipassing to the ends of the valve through said sin-all ports and building` up pressure at one of said ends of he valve until the freeexhaust port is opened by the piston and the valve being held by the pres`- sure of live motive fluid on one t'ace of the central flange of larger diameter until the valve is ready to be thrown.

2. In al fluid actuated rock drill, Vthe combination with a cylinder' and reciprocatingl piston, of a valve chest, a fluid actuated valve controlling the inlet supply and having a single central flange of larger diameter than the ends of the valve, which flange controls the passage of motive fluid from the ini let to both ends of the cylinder, crossed supply passages connecting the forward and rearward spaces in the valve chest between the central flange and the ends of the valve with the rearward and forward ends respectively of the cylinder, small ports connecting` the inlet directly with the spaces at the ends of the valve and a free exhaust port controlled by the piston, auxiliary exhaust ports communicating with the said supply passages and atmospheric leal; ports leading from t-he spaces at the ends of the valve both said auxiliary exhaust ports and leak ports being controlled by the ends of the valve, whereby the valve is thrown in a direction opposite to the direction of travel of the piston by the live motive fluid passing to the ends of the valve through said small ports and building up pressure at one of' said ends of the valve until the free exhaust port is opened by the piston and the valve being held by the pressure of' live motive fluid on one face ofl the central flange or" larger diameter until the valve is ready to be thrown.

3. In a fluid actuated rock drill, the combination with a cylinder and reciprocating piston, of a valve chest, a fluid actuated valve controlling the inlet supply and hav ing end heads and a single central flange of' larger diameter than the heads, which flange controls the passage of motive fluid from the inlet to both ends of the cylinder, crossed supply passages connecting the forward and rearward spaces in the valve chest between the central flange and the end heads with the rearward and forward ends respectively of the cylinder, a central annular inlet port in said valve chest into which the central flange of' the 7alve extends and seats and in which the said flange reciprocates, the edges of the said annular port also forming stops for limiting the movement of the valve, small ports connecting the inlet directly with the spaces at the ends of the valve, a free exhaust port controlled by the piston, auxiliary exhaust ports communieating with the said supply passages and atmospheric leale ports leading' from the spaces at the ends of the valve, both said Wauxiliary exhaust ports and leak ports being by the piston and the valve being held by controlled by the end heads of the valve the pressure of live motive fluid on the fece 10 whereby, the valve is thrown in e direction of the central flange of larger diameter uuopposite to the travel of the pistou by the til the valve is ready to'be thrown.

live motive Huid passing to the ends of the ln testimony whereof l have signed this valve through said small ports and building speeilieation.

up pressure at one of thel seid ends of the valve until the free exhaust port is opened FRED M. SLATER. 

